<?php
  $a = array(
    'key1' => 'value1',
    'key2' => 'value2'
    );
  
  foreach($a as $key => $val){
      echo '<br>'.$key.'='.$val;
  }
$chuoi = implode(',',$a);
print_r($chuoi);
$b = explode(',',$chuoi);
print_r($b);
$link_anh = 'https://www.google.com.vn/images/srpr/logo4w.png';
echo '<img src="'.$link_anh.'">';
?>
<img src="<?php echo $link_anh;?>">